Support multiple instances of brep in a single Apache instance

13 files changed, 171 insertions, 60 deletions

diff --git a/brep/database.cxx b/brep/database.cxx
index 9177b55..17605c5 100644
--- a/brep/database.cxx
+++ b/brep/database.cxx
@@ -4,40 +4,50 @@
 
 #include <brep/database>
 
+#include <map>
+
 #include <odb/pgsql/database.hxx>
 
 namespace brep
 {
+  namespace options
+  {
+    bool
+    operator< (const db& x, const db& y)
+    {
+      int r;
+      if ((r = x.db_user ().compare (y.db_user ())) != 0 ||
+          (r = x.db_password ().compare (y.db_password ())) != 0 ||
+          (r = x.db_name ().compare (y.db_name ())) != 0 ||
+          (r = x.db_host ().compare (y.db_host ())))
+        return r < 0;
+
+      return x.db_port () < y.db_port ();
+    }
+  }
+
   shared_ptr<odb::database>
   shared_database (const options::db& o)
   {
     using odb::pgsql::database;
-    static weak_ptr<database> db;
 
-    // In C++11, function-static variable initialization is guaranteed to be
-    // thread-safe, thought this doesn't seem to be enough in our case
-    // (because we are re-initializing the weak pointer).
-    //
-    if (shared_ptr<database> d = db.lock ())
-    {
-      if (o.db_user ()     != d->user ()     ||
-          o.db_password () != d->password () ||
-          o.db_name ()     != d->db ()       ||
-          o.db_host ()     != d->host ()     ||
-          o.db_port ()     != d->port ())
-        throw runtime_error ("shared database options mismatch");
-
-      return d;
-    }
-    else
+    static std::map<options::db, weak_ptr<database>> databases;
+
+    auto i (databases.find (o));
+    if (i != databases.end ())
     {
-      d = make_shared<database> (o.db_user (),
-                                 o.db_password (),
-                                 o.db_name (),
-                                 o.db_host (),
-                                 o.db_port ());
-      db = d;
-      return d;
+      if (shared_ptr<database> d = i->second.lock ())
+        return d;
     }
+
+    shared_ptr<database> d (
+      make_shared<database> (o.db_user (),
+                             o.db_password (),
+                             o.db_name (),
+                             o.db_host (),
+                             o.db_port ()));
+
+    databases[o] = d;
+    return d;
   }
 }
diff --git a/brep/mod-package-details b/brep/mod-package-details
index a99d271..0a86fc2 100644
--- a/brep/mod-package-details
+++ b/brep/mod-package-details
@@ -18,6 +18,14 @@ namespace brep
   class package_details: public module
   {
   public:
+    package_details () = default;
+
+    // Create a shallow copy (handling instance) if initialized and a deep
+    // copy (context exemplar) otherwise.
+    //
+    explicit
+    package_details (const package_details&);
+
     virtual bool
     handle (request&, response&);
 
diff --git a/brep/mod-package-details.cxx b/brep/mod-package-details.cxx
index fa07dd1..a5c2e3e 100644
--- a/brep/mod-package-details.cxx
+++ b/brep/mod-package-details.cxx
@@ -24,6 +24,18 @@
 using namespace odb::core;
 using namespace brep::cli;
 
+// While currently the user-defined copy constructor is not required (we don't
+// need to deep copy nullptr's), it is a good idea to keep the placeholder
+// ready for less trivial cases.
+//
+brep::package_details::
+package_details (const package_details& r)
+    : module (r),
+      options_ (r.initialized_ ? r.options_ : nullptr),
+      db_ (r.initialized_ ? r.db_ : nullptr)
+{
+}
+
 void brep::package_details::
 init (scanner& s)
 {
@@ -61,13 +73,8 @@ handle (request& rq, response& rs)
 
   MODULE_DIAG;
 
-  // The module options object is not changed after being created once per
-  // server process.
-  //
-  static const size_t res_page (options_->search_results ());
-  static const dir_path& root (options_->root ());
-  static const fragment& logo (options_->logo ());
-  static const vector<page_menu>& menu (options_->menu ());
+  const size_t res_page (options_->search_results ());
+  const dir_path& root (options_->root ());
 
   const string& name (*rq.path ().rbegin ());
   const string ename (mime_url_encode (name));
@@ -130,7 +137,7 @@ handle (request& rq, response& rs)
     <<     SCRIPT << " " << ~SCRIPT
     <<   ~HEAD
     <<   BODY
-    <<     DIV_HEADER (root, logo, menu)
+    <<     DIV_HEADER (root, options_->logo (), options_->menu ())
     <<     DIV(ID="content");
 
   if (full)
diff --git a/brep/mod-package-search b/brep/mod-package-search
index 7db976b..1730be4 100644
--- a/brep/mod-package-search
+++ b/brep/mod-package-search
@@ -18,6 +18,14 @@ namespace brep
   class package_search: public module
   {
   public:
+    package_search () = default;
+
+    // Create a shallow copy (handling instance) if initialized and a deep
+    // copy (context exemplar) otherwise.
+    //
+    explicit
+    package_search (const package_search&);
+
     virtual bool
     handle (request&, response&);
 
diff --git a/brep/mod-package-search.cxx b/brep/mod-package-search.cxx
index 7505e02..77a06b6 100644
--- a/brep/mod-package-search.cxx
+++ b/brep/mod-package-search.cxx
@@ -27,6 +27,18 @@
 using namespace odb::core;
 using namespace brep::cli;
 
+// While currently the user-defined copy constructor is not required (we don't
+// need to deep copy nullptr's), it is a good idea to keep the placeholder
+// ready for less trivial cases.
+//
+brep::package_search::
+package_search (const package_search& r)
+    : module (r),
+      options_ (r.initialized_ ? r.options_ : nullptr),
+      db_ (r.initialized_ ? r.db_ : nullptr)
+{
+}
+
 void brep::package_search::
 init (scanner& s)
 {
@@ -74,13 +86,8 @@ handle (request& rq, response& rs)
 
   MODULE_DIAG;
 
-  // The module options object is not changed after being created once per
-  // server process.
-  //
-  static const size_t res_page (options_->search_results ());
-  static const dir_path& root (options_->root ());
-  static const fragment& logo (options_->logo ());
-  static const vector<page_menu>& menu (options_->menu ());
+  const size_t res_page (options_->search_results ());
+  const dir_path& root (options_->root ());
 
   params::package_search params;
 
@@ -124,7 +131,7 @@ handle (request& rq, response& rs)
     <<     SCRIPT << " " << ~SCRIPT
     <<   ~HEAD
     <<   BODY
-    <<     DIV_HEADER (root, logo, menu)
+    <<     DIV_HEADER (root, options_->logo (), options_->menu ())
     <<     DIV(ID="content");
 
   session sn;
diff --git a/brep/mod-package-version-details b/brep/mod-package-version-details
index d102fdf..cfbcf94 100644
--- a/brep/mod-package-version-details
+++ b/brep/mod-package-version-details
@@ -18,6 +18,14 @@ namespace brep
   class package_version_details: public module
   {
   public:
+    package_version_details () = default;
+
+    // Create a shallow copy (handling instance) if initialized and a deep
+    // copy (context exemplar) otherwise.
+    //
+    explicit
+    package_version_details (const package_version_details&);
+
     virtual bool
     handle (request&, response&);
 
diff --git a/brep/mod-package-version-details.cxx b/brep/mod-package-version-details.cxx
index c9055a5..cbf9c86 100644
--- a/brep/mod-package-version-details.cxx
+++ b/brep/mod-package-version-details.cxx
@@ -25,6 +25,18 @@ using namespace std;
 using namespace odb::core;
 using namespace brep::cli;
 
+// While currently the user-defined copy constructor is not required (we don't
+// need to deep copy nullptr's), it is a good idea to keep the placeholder
+// ready for less trivial cases.
+//
+brep::package_version_details::
+package_version_details (const package_version_details& r)
+    : module (r),
+      options_ (r.initialized_ ? r.options_ : nullptr),
+      db_ (r.initialized_ ? r.db_ : nullptr)
+{
+}
+
 void brep::package_version_details::
 init (scanner& s)
 {
@@ -48,12 +60,7 @@ handle (request& rq, response& rs)
 
   MODULE_DIAG;
 
-  // The module options object is not changed after being created once per
-  // server process.
-  //
-  static const dir_path& root (options_->root ());
-  static const fragment& logo (options_->logo ());
-  static const vector<page_menu>& menu (options_->menu ());
+  const dir_path& root (options_->root ());
 
   auto i (rq.path ().rbegin ());
   version ver;
@@ -107,7 +114,7 @@ handle (request& rq, response& rs)
     <<     CSS_LINKS (path ("package-version-details.css"), root)
     <<   ~HEAD
     <<   BODY
-    <<     DIV_HEADER (root, logo, menu)
+    <<     DIV_HEADER (root, options_->logo (), options_->menu ())
     <<     DIV(ID="content");
 
   if (full)
diff --git a/brep/mod-repository-details b/brep/mod-repository-details
index 5f1e93f..411d9e6 100644
--- a/brep/mod-repository-details
+++ b/brep/mod-repository-details
@@ -18,6 +18,14 @@ namespace brep
   class repository_details: public module
   {
   public:
+    repository_details () = default;
+
+    // Create a shallow copy (handling instance) if initialized and a deep
+    // copy (context exemplar) otherwise.
+    //
+    explicit
+    repository_details (const repository_details&);
+
     virtual bool
     handle (request&, response&);
 
diff --git a/brep/mod-repository-details.cxx b/brep/mod-repository-details.cxx
index 0a88a16..f040be6 100644
--- a/brep/mod-repository-details.cxx
+++ b/brep/mod-repository-details.cxx
@@ -31,6 +31,18 @@ using namespace std;
 using namespace odb::core;
 using namespace brep::cli;
 
+// While currently the user-defined copy constructor is not required (we don't
+// need to deep copy nullptr's), it is a good idea to keep the placeholder
+// ready for less trivial cases.
+//
+brep::repository_details::
+repository_details (const repository_details& r)
+    : module (r),
+      options_ (r.initialized_ ? r.options_ : nullptr),
+      db_ (r.initialized_ ? r.db_ : nullptr)
+{
+}
+
 void brep::repository_details::
 init (scanner& s)
 {
@@ -54,12 +66,7 @@ handle (request& rq, response& rs)
 
   MODULE_DIAG;
 
-  // The module options object is not changed after being created once per
-  // server process.
-  //
-  static const dir_path& root (options_->root ());
-  static const fragment& logo (options_->logo ());
-  static const vector<page_menu>& menu (options_->menu ());
+  const dir_path& root (options_->root ());
 
   // Make sure no parameters passed.
   //
@@ -82,7 +89,7 @@ handle (request& rq, response& rs)
     <<     CSS_LINKS (path ("repository-details.css"), root)
     <<   ~HEAD
     <<   BODY
-    <<     DIV_HEADER (root, logo, menu)
+    <<     DIV_HEADER (root, options_->logo (), options_->menu ())
     <<     DIV(ID="content");
 
   transaction t (db_->begin ());
diff --git a/brep/mod-repository-root b/brep/mod-repository-root
index 254dfa3..f2c2ba0 100644
--- a/brep/mod-repository-root
+++ b/brep/mod-repository-root
@@ -23,6 +23,12 @@ namespace brep
   public:
     repository_root ();
 
+    // Create a shallow copy (handling instance) if initialized and a deep
+    // copy (context exemplar) otherwise.
+    //
+    explicit
+    repository_root (const repository_root&);
+
   private:
     virtual bool
     handle (request&, response&);
diff --git a/brep/mod-repository-root.cxx b/brep/mod-repository-root.cxx
index 61aa71b..7c27a60 100644
--- a/brep/mod-repository-root.cxx
+++ b/brep/mod-repository-root.cxx
@@ -58,6 +58,37 @@ namespace brep
   {
   }
 
+  repository_root::
+  repository_root (const repository_root& r)
+      : module (r),
+        //
+        // Deep/shallow-copy sub-modules depending on whether this is an
+        // exemplar/handler.
+        //
+        package_search_ (
+          r.initialized_
+          ? r.package_search_
+          : make_shared<package_search> (*r.package_search_)),
+        package_details_ (
+          r.initialized_
+          ? r.package_details_
+          : make_shared<package_details> (*r.package_details_)),
+        package_version_details_ (
+          r.initialized_
+          ? r.package_version_details_
+          : make_shared<package_version_details> (
+              *r.package_version_details_)),
+        repository_details_ (
+          r.initialized_
+          ? r.repository_details_
+          : make_shared<repository_details> (*r.repository_details_)),
+        options_ (
+          r.initialized_
+          ? r.options_
+          : nullptr)
+  {
+  }
+
   // Return amalgamation of repository_root and all its sub-modules option
   // descriptions.
   //
@@ -112,7 +143,7 @@ namespace brep
   {
     MODULE_DIAG;
 
-    static const dir_path& root (options_->root ());
+    const dir_path& root (options_->root ());
 
     const path& rpath (rq.path ());
     if (!rpath.sub (root))
diff --git a/brep/module b/brep/module
index 4ea5164..52106cd 100644
--- a/brep/module
+++ b/brep/module
@@ -88,7 +88,7 @@ namespace brep
 
     // Set to true when the module is successfully initialized.
     //
-    bool loaded_ {false};
+    bool initialized_ {false};
 
     // Implementation details.
     //
diff --git a/brep/module.cxx b/brep/module.cxx
index e8a824d..1257d82 100644
--- a/brep/module.cxx
+++ b/brep/module.cxx
@@ -30,7 +30,7 @@ namespace brep
 
     try
     {
-      if (!loaded_)
+      if (!initialized_)
       {
         MODULE_DIAG;
         fail << "not initialized, presumably due to misconfiguration";
@@ -187,7 +187,7 @@ namespace brep
   void module::
   init (const name_values& options, log& log)
   {
-    assert (!loaded_);
+    assert (!initialized_);
 
     log_ = &log;
 
@@ -207,7 +207,7 @@ namespace brep
       options::module o (s, cli::unknown_mode::fail, cli::unknown_mode::fail);
 
       verb_ = o.verbosity ();
-      loaded_ = true;
+      initialized_ = true;
     }
     catch (const server_error& e)
     {
@@ -236,7 +236,11 @@ namespace brep
   // Custom copy constructor is required to initialize log_writer_ properly.
   //
   module::
-  module (const module& m): module () {verb_ = m.verb_; loaded_ = m.loaded_;}
+  module (const module& m): module ()
+  {
+    verb_ = m.verb_;
+    initialized_ = m.initialized_;
+  }
 
 // For function func declared like this:
 // using B = std::string (*)(int);